H. Tachibana et al., Identification of a methylated tea catechin as an inhibitor of degranulation in human basophilic KU812 cells, BIOS BIOT B, 64(2), 2000, pp. 452-454
We examined the constituents of tea that had an inhibitory effect on the de
granulation process In the human basophilic cell line, KU812. Among the con
stituents purified from a extract of 'Benihomare' oolong tea by column chro
matography, a methylated (-)-epigallocatechin gallate ((-)-epigallocatechin
3-O-(3-O-methyl) gallate) was found to inhibit the degranulation of KU812
cells that had been stimulated with calcium ionophore A23187. The inhibitor
y effect of this methylated (-)-epigallocatechin gallate on degranulation w
as greater than that of (-)-epigallocatechin gallate. This result indicates
that methylation of (-)-epigallocatechin gallate may be an effective modif
ication for the catechin to inhibit degranulation from human basophils.